Diabetes is one of the most prevalent chronic diseases, characterized by impaired glucose metabolism and elevating blood glucose level. Diabetes is classified into two groups. Type 1 diabetes, or insulin dependent diabetes mellitus (IDDM), is caused by lack of insulin secreted from pancreatic beta-cells. Type 2 diabetes, or non-insulin dependent diabetes mellitus (NIDDM), is due to short of insulin action following both reduction of insulin secretion and insulin resistance. Insulin resistance is characterized by impaired insulin signaling in the insulin-target tissues such as liver, muscle, fat and pancreas itself. The Western diet with high-fat content leads to weight gain and obesity, which accelerates the development of insulin resistance and type 2 diabetes.
Presently, type 2 diabetes is treated with several medications that stimulate or replace the pancreatic beta-cell function, or enhance the insulin sensitivity of target tissues. However, the efficacy of these therapies often attenuates in the course of disease progression. Besides, the present agents for diabetes have several undesirable side effects such as hepatotoxicity, hypoglycemia, weight gain, gastrointestinal discomfort, lactic acidosis, and edema and so on. Accordingly, the more effective antidiabetic agent without these side effects has been desired earnestly.
On the other hand, the brain tissues are subject to ischemia over a long period of time in cerebrovascular disease, resulting in neuron cells necrosis and failure of regeneration, finally, cell deaths cause cerebral infarction. Although ischemic stroke is the third most common cause of death in the United States and Europe, the only currently approved medicinal treatment is administration of intravenous recombinant tissue plasminogen activator (rt-PA). Other than rt-PA, examples of the currently and mainly used as cerebral infarction treating agents include thrombolytic agents such as urokinase, anticoagulants such as warfarin and heparin, and free radical scavengers such as Radicut (edalabon) (product name: manufactured by Mitsubishi Pharma Corporation).
However, rt-PA shows its efficacy only when it is administered within 3 hours after onset of cerebral infarction, and with respect to anticoagulants, since it takes several days to express the anticoagulation action, the effects could hardly be said to be sufficient. In addition, since Radicut (product name: manufactured by Mitsubishi Pharma Corporation) sometimes causes serious side effects such as nephropathy, its use requires sufficient precautions. Thus, since the currently used cerebral infarction treating agents have problems in terms of their effect or toxicity and also have many limitations regarding their use, the development of useful therapeutic agents has been desired earnestly.
It was described that a compound represented by formula (K):

wherein L1k represents —C(O)—NH—, etc.; R1k represents heterocyclealkyl, etc.; R2k and R4k each independently represents cyano, etc.; R1k represents halogen, etc.; R5k represents alkoxy, etc.; is useful in antidiabetic agent and cerebral infarction treating agent as c-jun N-terminal kinase inhibitor (see reference such as patent literature 1).
Furthermore, it was described that a compound represented by formula (U):

wherein R1u, R2u and R3u each independently represents a hydrogen atom, alkoxy, etc.; W1u and W2u each independently represents N or CH; Xu represents NR4uCO, etc.; R4u represents a hydrogen, etc.; lu, mu and nu each independently represents a number of 0 or 1; is useful in an antasthmatic agent (see reference such as patent literature 2).
Furthermore, it has been described that a compound represented by formula (V):

wherein R1v, R2v and R3v each independently represents a hydrogen atom, alkoxy, etc.; W1v and W2v each independently represents N or CH; Xv represents NR4vCO, etc.; R4v represents a hydrogen, etc.; lv, my and nv each independently represents a number of 0 or 1; is useful in an anti-inflammatory agent (see reference such as patent literature 3).
Furthermore, it has been described that a compound represented by formula (W):

wherein R1w, R2w and R3w each independently represents a hydrogen atom, alkoxy, etc.; W1w and W2w each independently represents N or CH; Xw represents NR4wCO, etc.; R4W represents a hydrogen, etc.; lw, mw and nw each independently represents a number of 0 or 1; is useful in an HDAC inhibitor (see reference such as patent literature 4).
Furthermore, it has been described that a compound represented by formula (Y):

wherein R1y, R2y and R3y each independently represents a hydrogen atom, alkoxy, etc.; W1y and W2y each independently represents N or CH; XY represents NR4yCO, etc.; R4Y represents a hydrogen, etc.; ly, my and ny each independently represents a number of 0 or 1; is useful in a preventive/therapeutic agent for diseases attributable to erythropoietin production depression (see reference such as patent literature 5).
Furthermore, it has been described that a compound represented by formula (B):

wherein R1b represents carbocyclyl which may have a substituent(s), etc.; R2b represents heteroaryl which may have a substituent(s), etc.; Rab represents heteroaryl which may have a substituent(s), etc.; Xb represents C1-5 alkylene chain, etc.; Yb represents —C(O)—, etc.; Ring Ab represents aromatic 5-6 membered monocyclic ring which may have a substituent(s), etc.; mb represents a number of 0 or 1; nb represents a number of 0-5; is useful in CCR5 antagonists as therapeutic agents (see reference such as patent literature 6)
Furthermore, it has been described that a compound represented by formula (C):

wherein R3c represents alkyl, etc.; R4c represents alkyl, etc.; R5c and R6c each independently represents alkoxy which may have a substituent, etc.; R7c and R8c each independently represents alkyl, etc.; Ac represents phenyl substituted by phenyl or unsubstituted thienyl, etc.; Xc represents a bond, etc.; Yc represents alkylene, etc.; Zc represents alkylene, etc.; is useful in antiarrhythmic agent (see reference such as patent literature 7)
Furthermore, it has been described that a compound represented by formula (D):

wherein R1d represents heteroaryl which may have a substituent(s), etc.; R2d represents alkyl, etc.; R3d and R4d each independently represents hydrogen, etc.; R5d represents hydrogen, etc.; R6d represents heteroaryl which may have a substituent(s), etc.; Ad represents phenyl, etc.; L1d represents a bond, etc.; L2d represents methylene, etc.; L3d represents —C(O)—, etc.; Xd represents halogen, etc.; nd represents a number of 0-3; is useful in cannabinoid receptor ligands (see reference such as patent literature 8)
Furthermore, it has been described that a compound represented by formula (E):

wherein R4e represents heteroaryl, etc.; R5e and R6e each independently represents hydrogen, etc.; R8e and R9e each independently represents alkyl, etc.; R10e represents heteroaryl, etc.; Xe represents oxygen, etc.; me represents a number of 0-4; ye represents a number of 0-2; ze represents a number of 0-2; is useful in a preventive/therapeutic agent for Alzheimer's diseases (see reference such as patent literature 9)
Furthermore, it has been described that a compound represented by formula (F):

wherein R1f represents heteroaryl which may have a substituent(s), etc.; R2f represents alkyl which may have a substituent(s), etc.; R3f represents hydroxy, etc.; R4f represents heteroaryl which may have a substituent(s), etc.; Xf represents —C(O)— or —S(O)2—; Yf represents —CR5fR6f— or —CR5fR6fCR7fR8f—; R5f, R6f, R7f and R8f each independently represents alkyl, etc.; is useful in cannabinoid receptor 1 antagonists (see reference such as patent literature 10)
Furthermore, it has been described that a compound represented by formula (G):

wherein R1g and each independently represents heterocyclic ring which may have a substituent(s), etc.; Alk1g and Alk2g each independently represents bivalent hydrocarbon which may have a substituent(s), etc.; L1g represents 1-6 linker group, etc.; L2g represents a bond or 1-6 linker group, etc.; Het1g represents optionally substituted saturated heterocyclic ring containing nitrogen; mg and ng each independently represents a number of 0 or 1; is useful in a melanin concentrating hormone receptor antagonist (see reference such as patent literature 11)
Furthermore, it has been described that a compound represented by formula (J):

wherein, PJ represents alkyl which may have a substituent(s), etc.; QJ represents heterocyclyl ring which may have a substituent(s), etc.; ZJ represents nitrogen, oxygen or sulfur which may be oxidized; RJ represents phenyl which may have a substituent(s), etc.; XJ represents halogene, etc.; PJ is 0 to 4; is useful in a fungicides (see reference such as patent literature 12).
Furthermore, it has been described that a compound represented by formula (H):

wherein, R1ah, R1bh, R2h and R7h each in dependently represents hydrogen, etc; R3h and R4h each independently represents hydrogen, pyridine, etc; R6h represents alkoxy, amino, nitrile, etc; A1h and A2h each independently represents bond, —CONH—, etc; A3h represents bond, etc; Vh represents pyridine, etc; Wh represents piperidine, etc; Xh represents thiazole, etc; nh and ph each independently represents 0 to 4; rh represents 0 to 5; is useful in a farnesyl-protein transferase inhibitor (see reference such as patent literature 13)
Furthermore, it has been described that a compound represented by formula (L):

wherein, R1L, R2L, R3L, R4L, R5L and R7L each independently represents hydrogen, etc; R8L represents alkoxy, amino, nitrile, etc; AL represents carbon or nitrogen; BL, CL, DL and EL each independently represents carbon, nitrogen, oxygen or sulfur; FL each independently represents carbon or nitrogen; A1L and A2L each independently represents bond, —CONH—, etc; VL represents pyridine, etc; WL represents piperidine, etc; XL represents bond, etc; rL represents 0 to 5; nL and pL each independently represents 0 to 4; tL represents 0 or 1; qL represents 0 to 3; is useful in a farnesyl-protein transferase inhibitor (see reference such as patent literature 14) Furthermore, it has been described that a compound represented by formula (N):

wherein, WN represents piperidine, etc; R1N and R2N each independently represents hydrogen, etc; BN represents —CONH—(C0-2 alkylene)-, etc; QN and PN each independently represents pyridine which may have a substituent(s) such as alkoxy, amine, nitrile, etc; AN represents thiazole, etc; XN and YN each independently represents bond, C1-6 alkyl, etc; is useful in a mGluR5 positive allosteric modulator (see reference such as patent literature 15).
[Patent literature 1] WO2006083673
[Patent literature 2] WO2003020703
[Patent literature 3] U.S. Pat. No. 6,395,753
[Patent literature 4] WO2003086397
[Patent literature 5] WO2004052859
[Patent literature 6] WO2004054974
[Patent literature 7] WO2000061557
[Patent literature 8] WO2003042174
[Patent literature 9] WO2003049736
[Patent literature 10] US20060079556
[Patent literature 11] WO2004046110
[Patent literature 12] WO1998027080
[Patent literature 13] WO1997036876
[Patent literature 14] W01997036897
[Patent literature 15] WO2006129199